System, method, and computer program product for controlling stereo glasses shutters

ABSTRACT

A system, method, and computer program product are provided for controlling stereo glasses shutters. In use, a right eye shutter of stereo glasses is controlled to switch between a closed orientation and an open orientation. Further, a left eye shutter of the stereo glasses is controlled to switch between the closed orientation and the open orientation. To this end, the right eye shutter and the left eye shutter of the stereo glasses may be controlled such that the right eye shutter and the left eye shutter simultaneously remain in the closed orientation for a predetermined amount of time.

RELATED APPLICATION(S)

The present application claims priority of a provisional applicationfiled Mar. 29, 2006 under application Ser. No. 60/787,730, which isincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to video displays, and more particularlyto viewing stereo video and graphics images utilizing stereo shutterglasses.

BACKGROUND

Various display devices are equipped for both mono and stereo viewing.Unlike mono viewing, stereo viewing involves the display of separatecontent for the right and left human eye. Specifically, such stereoviewing requires the presentation of a separate image to the left andright human eye. In one particular type of stereo viewing, namely timesequential stereo, such left and right images are presented in analternating manner. To ensure a proper stereo viewing experience,alternating shutter glasses are also typically used which make the leftimage visible to the left eye and the right image to the right eye atthe appropriate time.

In the past, time sequential stereo viewing has worked well on CRTs andrelated displays [e.g. high frame rate (DLP) projectors, etc.]. However,time sequential stereo viewing has not shown promise with liquid crystaldisplays (LCDs), whether flat-panel or in the form of a projector, dueto several issues. For example, a slow response time of pixels in LCDenvironments causes ‘ghosting’ of the left image in the right view, andvisa versa. Still yet, the nature of the LCD update processunfortunately results in only short periods of time when the right imageand left image may be present in their entirety, as will now bedescribed in more detail.

FIG. 1A illustrates hypothetical shortcomings that would exist if stereoviewing were attempted utilizing an LCD. As shown in the presenthypothetical example, the LCD would receive pixels in raster scan order(i.e. left to right, line by line from top to bottom, etc.) over a cable10, such as a digital video interface (DVI) or video graphics array(VGA) cable. A first left image L1 intended for viewing by a left eye issent over the cable 10 first. Thereafter, there is a pause intransmission called the vertical blanking interval VBI. Next, a firstright image R1 intended for the right eye is sent, and so forth.

Unlike CRTs and other related displays, LCD pixels have individualcapacitive storage elements that cause each pixel to retain its colorand intensity until it is update by LCD driver-related electrons whichaddresses pixels in raster order. Thus, at time T1, when part of thefirst right image R1 has been sent, the actual image emitted from theLCD screen includes the ‘not yet overwritten’ (e.g. red) part of firstleft image L1 at the bottom, and the newly written (e.g. green) part ofthe first right image R1. Further, at T2, and, in fact, for the entirevertical blanking interval VBI starting at time T2, the display includesonly the first right image R1. At time T3, the first right image R1 hasbeen partially overwritten by a second left image L2, in the mannershown. To this end, if the display content at time T1 and T3 were shownto the left or right eye, such eye would unfortunately receive content,at least in part, not intended for such eye.

As mentioned earlier, stereo glasses equipped with right and left eyeshutters are often employed to ensure that the proper eye views theappropriate image, during stereo viewing. As shown, in the presenthypothetical example, after the first left image L1 is displayed, a lefteye shutter control 20 switches the left shutter to an open orientation(during which a right shutter is maintained in a closed orientation).Similarly, after the first right image R1 is displayed, a right eyeshutter control 30 switches the right shutter to an open orientation (atwhich time the left shutter toggles to and is maintained in a closedorientation).

Again, each eye unfortunately, receives content, at least in part, notintended for such eye for a sizeable portion of the duration in whichthe associated shutter is in the open orientation, resulting inunacceptable stereo viewing. There is thus a need for overcoming theseand/or other problems associated with the prior art.

SUMMARY

A system, method, and computer program product are provided forcontrolling stereo glasses shutters. In use, a right eye shutter ofstereo glasses is controlled to switch between a closed orientation andan open orientation. Further, a left eye shutter of the stereo glassesis controlled to also switch between the closed orientation and the openorientation. In use, the right eye shutter and the left eye shutter ofthe stereo glasses may be controlled such that the right eye shutter andthe left eye shutter simultaneously remain in the closed orientation fora predetermined amount of time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates hypothetical shortcomings that would exist if stereoviewings were attempted utilizing a liquid crystal display (LCD).

FIG. 1B illustrates an exemplary computer system in which the variousarchitecture and/or functionality of various embodiments may beimplemented.

FIG. 2 shows an exemplary timing or enhancing a viewing experience whendisplay content is viewed utilizing stereo glasses, in accordance withone embodiment.

FIG. 3 shows a method for increasing a vertical blanking interval forenhancing a viewing experience when display content is viewed utilizingstereo glasses, in accordance with one embodiment.

FIG. 4 shows a method for increasing a vertical blanking interval forenhancing a viewing experience when display content is viewed utilizingstereo glasses, in accordance with another embodiment.

FIG. 5 shows an exemplary timing for use when display content is viewedutilizing stereo glasses and an LCD or the like, in accordance with yetanother embodiment.

DETAILED DESCRIPTION

FIG. 1 illustrates an exemplary computer system 100 in which the variousarchitecture and/or functionality of different embodiments may beimplemented. As shown, a computer system 100 is provided including atleast one host processor 101 which is connected to a communication bus102. The computer system 100 also includes a main memory 104. Controllogic (software) and data are stored in the main memory 104 which maytake the form of random access memory (RAM).

The computer system 100 also includes a graphics processor 106 and adisplay 108 in the form of a liquid crystal display (LCD), digital lightprocessing (DLP) display, liquid crystal on silicon (LCOS) display,plasma display, or other similar display. In one embodiment, thegraphics processor 106 may include a plurality of shader modules, arasterization module, etc. Each of the foregoing modules may even besituated in a single semiconductor platform to form a graphicsprocessing unit (GPU).

In the present description, a single semiconductor platform may refer toa sole unitary semiconductor-based integrated circuit or chip. It shouldbe noted that the term single semiconductor platform may also refer tomulti-chip modules with increased connectively which simulate on-chipoperation, and make a substantial improvements over utilizing aconventional central processing unit (CPU) and bus implementation. Ofcourse, the various modules may also be situated separately or invarious combinations of semiconductor platforms per the desires of theuser.

The computer system 100 may also include a secondary storage 110. Thesecondary storage 110 includes, for example, a hard disk drive and/or aremovable storage drive, representing a floppy disk drive, a magnetictape drive, a compact disk drive, etc. The removable storage drive readsfrom and/or writes to a removable storage unit in a well known manner.

Computer programs, or computer control logic algorithms, may be storedin the main memory 104 and/or the secondary storage 110. Such computerprograms when executed, enable the computer system 100 to performvarious functions. Memory 104, storage 110 and/or any either storage arepossible examples of computer-readable media.

Further included is a pair of stereo glasses 111 capable of being wornon a face of a user. While the stereo glasses 111 are shown to includetwo elongated members for supporting the same on the face of the user,it should be noted that other constructions (e.g. member-less design,head strap, helmet, etc.) may be used to provide similar or any othertype of support. As further shown, the stereo glasses 111 also include aright eye shutter 114 and a left eye shutter 113.

Both the right eye shutter 114 and left eye shutter 113 are capable ofboth an open orientation and a closed orientation. In use, the openorientation allows more light therethrough with respect to the closedorientation. Of course, such orientations may be achieved by any desiredmechanical, electrical, optical, and/or any other mechanism capable ofcarrying out the above functionality.

For control purposes, the stereo glasses 111 may be coupled to a stereocontroller 119 via a cable 118 (or without the cable 118 in a wirelessenvironment). The stereo controller 119 is, in turn, coupled between thegraphics processor 106 and the display 108 for carrying out thefunctionality to be set forth hereinafter. While the stereo controller119 is shown to reside between the graphics processor 106 and thedisplay 108, it should be noted that the stereo controller 119 mayreside in any location associated with the computer system 100, thestereo glasses 111, and/or even in a separate module, particularly (butnot necessarily) in an embodiment where the graphics processor 106 isattached to a separate interface [e.g. universal serial bus (USB), etc.]on the computer system 100. In one embodiment, the display 108 may bedirectly connected to the computer system 100, and the stereo controller119 may further be directly connected to the computer system 100 via aUSB interface. Still yet, the stereo controller 119 may comprise anyhardware and/or software capable of the providing the desiredfunctionality.

Specifically, in some embodiments, the right eye shutter 114 and lefteye shutter 113 are controlled to switch between the closed orientationand the open orientation. For reasons that will be apparent hereinafter,the right eye shutter 114 and left eye shutter 113 of the stereo glasses111 may be controlled such that the right eye shutter 114 and left eyeshutter 113 simultaneously remain in the closed orientation for apredetermined amount of time. In particular, as will soon becomeapparent, such technique reduces a duration in which each eye receivescontent, at least in part, not intended for such eye, resulting inenhanced stereo viewing of content on the display 108.

In addition to and/or instead of the foregoing technique, the stereocontroller 119, the display 108, and/or any other appropriatehardware/software associated with the computer system 100 may beequipped with functionality for adapting the display 108 in a way thatenhances a viewing experience when display content is viewed utilizingthe stereo glasses 111. Specifically, a duration of a vertical blankinginterval associated with received display content may be increased forenhancing a viewing experience when the display content is viewedutilizing the stereo glasses 111.

In the context of the present description, the vertical blankinginterval may refer to any time duration between the display of contentintended for viewing by a right eye and a left eye. In one optionalembodiment, such vertical blanking interval may refer to a time durationin which blank lines (and/or other information) are sent across aninterface to the display 108. Still yet, in another embodiment, thevertical blanking interval may refer to a time when the content is heldon the display 108 and no update occurs. By enlarging the verticalblanking interval (e.g. by sending more blank lines across theaforementioned interface, etc.), the content may be displayed longer forallowing the stereo glasses 111 to remain open longer, thus increasingthe apparent brightness to the user, in accordance with one optionalembodiment.

More illustrative information will now be set forth regarding variousoptional architecture and features with which the foregoingfunctionality may or may not be implemented, per the desires of theuser. It should be strongly noted that the following information is setforth for illustrative purposes and should not be construed as limitingin any manner. Any of the following features may be optionallyincorporated with or without the exclusion of other features described.

For example, in one embodiment, the architecture and/or functionality ofthe various following figures may be implemented in the context of thehost processor 101, graphics processor 106, a chipset (i.e. a group ofintegrated circuits designed to work and sold as a unit for performingrelated functions, etc.), and/or any other integrated circuits for thatmatter. Still yet, the architecture and/or functionality of the variousfollowing figures may be implemented in the context of a generalcomputer system, a circuit board system, a game console system dedicatedfor entertainment purposes, an application-specific system, and/or anyother desired system.

FIG. 2 shows an exemplary timing 200 for enhancing a viewing experiencewhen display content is viewed utilizing stereo glasses, in accordancewith one embodiment. As an option, the present timing 200 may beimplemented in the context of the computer system 100 of FIG. 1B. Ofcourse, however, the timing 200 may be used in any desired environment.Still yet, the above definitions apply during the following description.

As shown, a display (e.g. display 108 of FIG. 1, etc.) receives displaycontent over a communication medium 201, such as a digital videointerface (DVI) or video graphics array (VGA) cable, or another mediumcapable of communicating the display content, for that matter. In thecontext of the present description, such display content may includepixel-related information, images(s), and/or any other content orcomponent thereof at any stage of processing capable of being displayed.In FIG. 2, a first left image L1 intended for viewing only by a left eyeis shown to be sent over the communication medium 201 first. Thereafter,there is a pause in transmission, namely the vertical blanking intervalVBI. Next, a first right image R1 intended for only the right eye isthen sent, and so forth.

As further shown, a right eye shutter and left eye shutter of stereoglasses (e.g. stereo glasses 111, etc.) are controlled independently. Inone embodiment, this may be accomplished utilizing a right eye controlsignal 206 for controlling the right eye shutter and a left controlsignal 208 for controlling the left eye shutter.

Specifically, the left eye shutter of the stereo glasses may becontrolled such that the left eye shutter is in an open orientation atleast for the duration of a first set of vertical blanking intervals210, which follow receipt of display content intended for a left eye. Ina similar manner, the right eye shutter of the stereo glasses may becontrolled such that the right eye shutter is in the open orientation atleast for the duration of a second set of vertical blanking intervals213, which follow receipt of display content intended for a right eye.As shown, the first set of vertical blanking intervals 210 alternatewith the second set of vertical blanking intervals 213, and they bothoccur between periods during which right eye content or left eye contentis received from a content source.

In other embodiments (e.g. particularly in the case of wireless stereoglasses, etc.), the right eye shutter and the left eye shutter of thestereo glasses may be controlled utilizing a plurality of signals (e.g.codes, etc.). In such embodiments, one of such signals may bespecifically allocated to cause the right eye shutter and the left eyeshutter to simultaneously transition to and remain in the closedorientation. Of course, separate signals may be used to close only theright eye shutter, the left eye shutter, etc.

To this end, a right eye shutter and left eye shutter of the stereoglasses may be controlled such that the right eye shutter and left eyeshutter simultaneously remain in the closed orientation for apredetermined amount of time 209. As shown, such predetermined amount oftime 209 represents a time during which the first left image L1 has beenpartially overwritten by the first right image R1. Thus, by ensuringthat both the right eye shutter and left eye shutter of the stereoglasses simultaneously remain in the closed orientation during suchtime, the right eye content is prevented from reaching the left eye andthe left eye content is prevented form reaching the right eye.

In the embodiment illustrated in FIG. 2, the left eye shutter of thestereo glasses may be controlled such that the left eye shutter is inthe open orientation only for the duration of the first set of verticalblanking intervals 210 (i.e. when only left eye content is beingdisplayed, etc.). Further, the right eye shutter of the stereo glassesmay be controlled such that the right eye shutter is in the openorientation only for the duration of the second set of vertical blankingintervals 213 (i.e. when only right eye content is being displayed,etc.). Thus, such predetermined amount of time 209 represents an entiretime frame in which the first left image L1 has been partiallyoverwritten by the first right image R1, and so on.

In other embodiments, however, the right eye shutter and the left eyeshutter of the stereo glasses may be controlled such that the shutterseach remain in the open orientation for an adjustable time period (withthe predetermined amount of time 209 being decreased) to permitadditional light though each respective shutter. See time period 210,for example. To this end, the eyes of the user may be subjected to morelight, thereby enhancing a perceived brightness of an image.

In other words, the left eye shutter of the stereo glasses may becontrolled such that the left eye shutter is in the open orientation fora period that exceeds the duration of the first set of vertical blankingintervals 210. Similarly, the right eye shutter of the stereo glassesmay be controlled such that the right eye shutter is in the openorientation for a period that exceeds the duration of the second set ofvertical blanking intervals 213. Of course, one trade off associatedwith such option involves increasing the duration in which each eyereceives content, at least in part, not intended for such eye.Specifically, at least a portion of left eye content may be displayedwhen the right eye shutter is in the open orientation, and visa-versa.

As set forth reference to FIG. 1B, the duration of the vertical blankinginterval VBI associated with received display content may be increasedfor enhancing a viewing experience when the display content is viewedutilizing the stereo glasses. By increasing the duration of the verticalblanking interval VBI, the time period is increased during which eacheye receives content wholly intended for such eye, resulting in enhancedstereo viewing of content on the display.

It should be noted that the vertical blanking interval VBI may beincreased in any desired manner. For example, before a content coursesends data to the display, appropriate display timing specifications maybe consulted. This may be accomplished using any desired interface [e.g.extended display data channel/extended display identification data(E-DCC/EDID), video electronics standards organization (VESA) interface,etc.] using the communication medium 201. To this end, the contentsource may choose one of many established/standard timings and/ortailored timings to send the content, where such timing allows forvertical blanking interval VBI augmentation. Such timings may further beprovided/maintained by the manufacturer of the stereo glasses, graphicsprocessor that drives the images using configuration files, etc. Moreinformation regarding various exemplary techniques that may bespecifically used to increase the duration of the vertical blankinginterval VBI in such manner will be set forth in greater detail duringreference to subsequent figures.

FIG. 3 shows a method 300 for increasing a vertical blanking intervalfor enhancing a viewing experience when display content is viewedutilizing stereo glasses, in accordance with one embodiment. As anoption, the present method 300 may be carried out in the context of thecomputer system 100 of FIG. 1B and/or the timing 200 of FIG. 2. Ofcourse, however, the method 300 may be implemented in any desiredenvironment. Again, the definitions introduced hereinabove apply duringthe following description.

As shown, a display (e.g. display 108 of FIG. 1, etc.) is driven at anative resolution. See operation 303. Such native resolution may referto the resolution at which the display is designed to display contentwithout conversion. The native resolution is typically based on anactual number of cells in the display.

Next, a rate at which pixels are sent to the display is increased,utilizing a pixel clock. Specifically, in one embodiment, pixels may betransmitted for display purposes using a highest possible pixel clock.See operation 304. In one exemplary embodiment, such maximum pixel clockmay include that which a standard governing a connection cable supports(e.g. 165 Mpix/s for a single link DVI cable, 330 Mpix/s for a dual linkDVI cable, etc.). In another embodiment, the foregoing highest possiblepixel clock may include a pixel clock limit indicated by the display inrelated EDID information. Such limit may be the same as, or lower than aDVI cable clock limit.

Still yet, a horizontal blanking interval associated with the display isdecreased, as indicated in operation 306. In the context of the presentdescription, the horizontal blanking interval refers to an intervalduring which processing of successive lines returns from right to left.In one embodiment, the horizontal blanking interval may be chosen to beas small as possible. By maximizing the pixel clock and minimizing thehorizontal blanking interval in the foregoing manner, the verticalblanking interval duration may be maximized. The manner in which this isaccomplished will become more readily apparent during the description ofan example to be set forth later.

An alternate technique for increasing the vertical blanking interval(besides increasing the pixel clock, etc.) may involve the reduction ofa display refresh rate. For example, a display designed for a 100 Hzrefresh rate with a low vertical blanking interval may be used at 85 Hzwith a 19% vertical blanking interval, in one illustrative embodiment.

In various embodiments, the display may be specifically equipped with aplurality of additional timings for increasing the duration of thevertical blanking interval. While the display may be equipped with theadditional timings in any one of a variety of ways, it may beaccomplished, in one embodiment, by including the same in softwarestored in memory of the display. In use, such additional timings mayeach be adapted for either decreasing a horizontal blanking intervalassociated with the display and/or increasing a rate at which pixels aresent to the display.

Table 1 illustrates one exemplary timing that may be added in theforegoing manner. Of course, such timing is set forth for illustrativepurposes only and should not be construed as limiting in any manner. Forexample, in a VGA environment, such a table may be updated inassociation with a display while, in a DVI environment, no such changemay be necessary.

TABLE 1 Timing Name 1280 × 1024 75 S Computed: Hor Pixels 1280 VerPixels 1024 Hor Frequency 105.00 kHz Ver Frequency 75.00 Hz Pixel Clock139.44 MHz HBlank 3.6% of Htotal VBlank 26.9% of Vtotal Hor Total Time1328 Pixels Hor Addr Time 1280 Pixels Hor Blank Start 1280 Pixels HorBlank Time 48 Pixels Hor Sync Time 16 Pixels Hor Sync Start 1288 PixelsH Right Border 0 Pixels H Front Porch 8 Pixels Hor Sync Time 16 Pixels HBack Porch 24 Pixels H Left Border 0 Pixels Ver Total Time 1400 LinesVer Addr Time 1024 Lines Ver Blank Start 1024 Lines Ver Blank Time 376Lines Ver Sync Start 1040 Lines V Bottom Borde 0 Lines V Front Porch 16Lines Ver Sync Time 112 Lines V Back Porch 248 Lines V Top Border 0Lines

It should be noted that the aforementioned horizontal blanking intervalis less important in the context of LCD, DLP-type displays, etc.,thereby providing an opportunity for sacrificing the same to extend thevertical blanking interval. In particular, in CRT-type displays, suchhorizontal blanking is typically augmented (e.g. in the range of 15-25%,etc.) to allow re-tracing to a beginning of a particular scan line. Forexample, a CRT-type display may display a first line of X number ofpixels after which a horizontal blanking interval may be used to providetime for the display to re-trace to the beginning of the scan line sothat another line of X number of pixels may be displayed, and so forth.

Equation #1 illustrates the interrelationship between the horizontalblanking interval and the vertical blanking interval.f _(pix)=(pixels_(—) X-direction+HBI)*(pixels_(—) Y-direction+VBI)*f_(v)  Equation #1where

f_(pix)=pixel rate

HBI=# of pixels in horizontal blanking interval

pixels_X-direction=# of pixels in X-direction for predeterminedresolution

VBI=# of pixels associated in vertical blanking interval

pixels_Y-direction=# of pixels in Y-direction for predeterminedresolution

f_(v)=refresh rate

As shown, a horizontal blanking interval may be sacrificed for anextended vertical blanking interval (particularly with LCD, DLP-typedisplays, etc.), without necessarily affecting the pixel rate and therefresh rate.

Thus, in one embodiment, the foregoing timing of Table 1 may provide analternate 1280×1024 75 Hz stereo compatible timing specification thatmay co-exist with existing VESA 1280×1024 75 Hz timing specifications.In such exemplary embodiment, the existing 1280×1024 75 Hz VESA timingemploys 24.2% of available time for horizontal blanking and 3.9% forvertical blanking, whereas the stereo compatible timing employs close to27% of available time for vertical blanking and less than 4% forhorizontal blanking.

FIG. 4 shows a method 400 for increasing a vertical blanking intervalfor enhancing a viewing experience when display content is viewedutilizing stereo glasses, in accordance with another embodiment. As anoption, the present method 400 may be carried out in the context of thecomputer system 100 of FIG. 1B and/or the timing 200 of FIG. 2. Ofcourse, however, the method 400 may be implemented in any desiredenvironment. Yet again, the definitions introduced hereinabove applyduring the following description.

As shown, a display (e.g. display 108 of FIG. 1, etc.) may be set at alower resolution during use. See operation 402. Still yet, the displaymay be run at a predetermined speed for extending the vertical blankinginterval. Note operation 404. An example of such technique is set forthbelow.

Specifically, in one optional embodiment, a display may be provided thatis designed for a 1600×1200 resolutions, but is used at a lowerresolution such as 1024×768. If such display supports the 1600×1200resolution at 60 Hz (in accordance with the VESA standard), it is likelycapable of 162 Mpix/s (in any resolution). Thus, by sending the display1024*768 pixels with a 162 MHz pixel clock, an entire image (assuming100 pixel horizontal blanking) may be send in 5.33 ms(1144*768*6.173e-9). Since images at 60 Hz are received every 16.66msec, the vertical blanking interval may thus be extended to 11.33 msec(16.66−5.33). To this end, each shutter of a pair of stereo glasses(e.g. stereo glasses 111 of FIG. 1, etc.) may remain in an openorientation for 11.33 msec out of every 33.33 msec, thereby providing aduty cycle of 34% (out of a theoretical maximum of 50%).

In one embodiment, the foregoing functionality of FIGS. 3-4 mayoptionally be provided by utilizing a controller (e.g. stereo controller119 of FIG. 1, etc.) coupled to the display. In the context of thepresent embodiment, such controller may be employed for tapping signalsin a cable feeding the display to retrieve triggering information forthe glasses (e.g. stereo glasses 111 of FIG. 1, etc.). Such triggeringinformation may be derived from a vertical synchronized in the cable,along with left/right eye shutter identifying information associatedwith the content (e.g. white line codes, etc.) or software-providedcontrol signals (e.g. DDC signal, etc.).

In another embodiment, the method 300 of FIG. 3 and the method 400 ofFIG. 4 may be provided by interrupting two I2C® interface wires thattypically carry EDID standard information. In an embodiment where thecontroller takes the form of a microcontroller, such hardware may readoriginal display EDID information and present modified EDID informationto the associated computer system. In such embodiment, drivers that usethe EDID information to compute timing settings need not necessarily bemodified.

FIG. 5 shows an exemplary timing 500 for use when the display content isviewed utilizing stereo glasses and an LCD or the like, in accordancewith yet another embodiment. As an option, the present timing 500 may beimplemented in the context of the computer system 100 of FIG. 1B and/orthe timing of 200 of FIG. 2. Of course, however, the timing 500 may beused in any desired environment.

In the present embodiment, display content sent to a display (e.g.display 108 of FIG. 1, etc.) in operation 502 may, in turn, be receivedand buffered in the manner shown in operation 504. As an option, suchbuffering may be carried out utilizing buffer memory (e.g. DRAM, etc.)resident in the display or in any other location, for that matter.

Once the display content for a particular eye is received and bufferedin operation 504, it may be sent from the buffer to the display, asfurther indicated operation 504. To this end, the display may paint theparticular display content currently being sent from the buffer. Noteoperation 506. Note that, after the display content for a particular eyehas been sent and painted, such display content may be held in themanner shown.

By this design, the left and right eye shutter of a pair of stereoglasses (e.g. stereo glasses 111 of FIG. 1, etc.) may be opened duringthe time period when the corresponding display content is being held.Note operations 508 and 510, respectively. By buffering the displaycontent in operation 504 in the foregoing manner, any lengthy timenecessary for the display content to cross the cable to the buffer isavailable, thus keeping the pixel clock low. Further, when the displaycontent is buffered and ready for display, the display content may betransferred rapidly to the display, so that it may be held and displayedto a respective eye for a longer time. Thus, a stable time of thedisplay content may be increased by buffering the display content in theforegoing manner, while avoiding a need to increase the verticalblanking interval on a display interface cable, etc.

In summary, display content received from a content source may bebuffered for a predetermined eye until a full image of display contentfor such eye is available. While such buffering is taking place,previous display content for the other eye may be displayed. When suchbuffering is complete and the image is stable, the full image of displaycontent for such eye may be transferred from the buffer to the displayfor the duration of the vertical blanking interval or longer. Further,such transfer may be carried out at a maximum pixel rate that thedisplay is capable of handling internally so that the vertical blankinginterval is capable of being maximized. If such interval is too short,additional buffering that can temporarily receive and store the nextincoming image may be employed. To this end, a duration in which the eyeshutters may be maintained in the open orientation may be extended (andhence maximize screen brightness, etc.).

Strictly as an option, a backlight of the display may be activated onlywhen at least one of the shutters is in the open orientation. Thisfeature may be applied in the context of flashing or scrollingbacklights. In the case of a flashing backlight, the backlight may beflashed for 30% of the time (for example), but may also use a light withtriple the magnitude, in order to provide normal light output. To thisend, the present feature may be used to avoid wasting light (andassociated power) when the shutters are closed, and further avoidexcessive heat. As an option, the foregoing backlight activation may beperformed utilizing techniques set forth in a co-pending applicationfiled Jan. 27, 2005 under application Ser. No. 11/045,239, which isincorporated herein by reference in its entirety.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, and notlimitation. For example, any of the network elements may employ any ofthe desired functionality set forth hereinabove. Thus, the breadth andscope of a preferred embodiment should not be limited by any of theabove-described exemplary embodiments, but should be defined only inaccordance with the following claims and their equivalents.

1. A method, comprising: controlling a right eye shutter of stereoglasses to switch between a closed orientation and an open orientation;and controlling a left eye shutter of the stereo glasses to switchbetween the closed orientation and the open orientation; wherein theright eye shutter and the left eye shutter of the stereo glasses arecontrolled such that the right eye shutter and the left eye shuttersimultaneously remain in the closed orientation for a predeterminedamount of time; wherein the right eye shutter of the stereo glasses iscontrolled such that the right eye shutter is in the open orientationonly for a duration of a first set of vertical blanking intervals, andthe left eye shutter of the stereo glasses is controlled such that theleft eye shutter is in the open orientation only for a duration of asecond set of vertical blanking intervals; wherein the predeterminedamount of time represents at least one of a time during which a leftimage has been partially overwritten on a display by a right imageintended for the right eye shutter and a time during which the rightimage has been partially overwritten on a display by a left imageintended for the left eye shutter.
 2. The method as recited in claim 1,wherein the right eye shutter and the left eye shutter of the stereoglasses are controlled independently.
 3. The method as recited in claim2, wherein the right eye shutter and the left eye shutter of the stereoglasses are controlled independently utilizing a first control signalfor controlling the right eye shutter and a second control signal forcontrolling the left eye shutter.
 4. The method as recited in claim 1,wherein the right eye shutter and the left eye shutter of the stereoglasses are controlled utilizing a plurality of signals, one of whichcauses the right eye shutter and the left eye shutter to simultaneouslytransition to and remain in the closed orientation.
 5. The method asrecited in claim 1, wherein the right eye shutter and the left eyeshutter of the stereo glasses are controlled to permit stereo viewing ofcontent on a display.
 6. The method as recited in claim 5, wherein thedisplay includes a liquid crystal display.
 7. The method as recited inclaim 1, wherein the first set of vertical blanking intervals alternatewith the second set of vertical blanking intervals.
 8. The method asrecited in claim 1, wherein the first set of vertical blanking intervalsand the second set of vertical blanking intervals occur between periodsduring which right eye content or left eye content is received from acontent source.
 9. The method as recited in claim 1, wherein theduration of the first set of vertical blanking intervals and theduration of the second set of vertical blanking intervals is increased.10. The method as recited in claim 1, wherein the right eye shutter ofthe stereo glasses is controlled such that the right eye shutter is inthe open orientation when only right eye content is being displayed, andthe left eye shutter of the stereo glasses is controlled such that theleft eye shutter is in the open orientation when only left eye contentis being displayed.
 11. The method as recited in claim 1, wherein theright eye shutter and the left eye shutter of the stereo glasses arecontrolled such that the right eye shutter and the left eye shutter eachremain in the open orientation for an adjustable time period.
 12. Themethod as recited in claim 11, wherein the adjustable time period isadjusted to permit additional light through the right eye shutter andthe left eye shutter.
 13. The method as recited in claim 1, wherein thecontrolling is performed utilizing a controller connected to a computersystem via a universal serial bus interface.
 14. The method as recitedin claim 1, wherein a backlight of the display is activated only whenone of the shutters is in the open orientation.
 15. A computer programproduct embodied on a computer readable medium, comprising: computercode for controlling a right eye shutter of stereo glasses to switchbetween a closed orientation and an open orientation; and computer codefor controlling a left eye shutter of the stereo glasses to switchbetween the closed orientation and the open orientation; wherein thecomputer program product is operable such that the right eye shutter andthe left eye shutter of the stereo glasses are controlled such that theright eye shutter and the left eye shutter simultaneously remain in theclosed orientation for a predetermined amount of time; wherein thecomputer program product is operable such that the right eye shutter ofthe stereo glasses is controlled such that the right eye shutter is inthe open orientation only for a duration of a first set of verticalblanking intervals, and the left eye shutter of the stereo glasses iscontrolled such that the left eye shutter is in the open orientationonly for a duration of a second set of vertical blanking intervals;wherein the predetermined amount of time represents at least one of atime during which a left image has been partially overwritten on adisplay by a right image intended for the right eye shutter and a timeduring which the right image has been partially overwritten on a displayby a left image intended for the left eye shutter.
 16. A system,comprising a graphics processor; and a controller in communication withthe graphics processor, the controller for controlling a right eyeshutter and a left eye shutter of stereo glasses to switch between aclosed orientation and an open orientation; wherein the system isoperable such that the right eye shutter and the left eye shutter of thestereo glasses are controlled such that the right eye shutter and theleft eye shutter simultaneously remain in the closed orientation for apredetermined amount of time; wherein the system is operable such thatthe right eye shutter of the stereo glasses is controlled such that theright eye shutter is in the open orientation only for a duration of afirst set of vertical blanking intervals, and the left eye shutter ofthe stereo glasses is controlled such that the left eye shutter is inthe open orientation only for a duration of a second set of verticalblanking intervals; wherein the predetermined amount of time representsat least one of a time during which a left image has been partiallyoverwritten on a display by a right image intended for the right eyeshutter and a time during which the right image has been partiallyoverwritten on a display by a left image intended for the left eyeshutter.
 17. The system as recited in claim 16, wherein the graphicsprocessor is in communication with a display and a central processingunit via a bus.
 18. The method as recited in claim 1, wherein thepredetermined amount of time includes a time period between a verticalblanking interval preceding the time period and a vertical blankinginterval following the time period.
 19. The method as recited in claim5, wherein the content is buffered utilizing buffer memory resident inthe display.
 20. The method as recited in claim 5, wherein the contentis buffered utilizing buffer memory resident in a location other than acomputer system, the computer system including a central processing unitand memory connected via at least one bus.
 21. The method as recited inclaim 20, wherein the location other than the computer system includesthe display.
 22. The system as recited in claim 16, wherein the righteye shutter and the left eye shutter of the stereo glasses arecontrolled to permit stereo viewing of content on a display.
 23. Thesystem as recited in claim 22, wherein the content is buffered utilizingbuffer memory resident in the display.
 24. The system as recited inclaim 22, wherein the content is buffered utilizing buffer memoryresident in a location other than a computer system, the computer systemincluding a central processing unit and memory connected via at leastone bus.
 25. The system as recited in claim 24, wherein the locationother than the computer system includes the display.